Shun-Jen Tan - Academia.edu (original) (raw)

Papers by Shun-Jen Tan

Taiwanese Journal of Obstetrics and Gynecology, 2012

European journal of gynaecological oncology, 2010

Management of patients with recurrent or advanced cervical cancer is a challenge. Concurrent chem... more Management of patients with recurrent or advanced cervical cancer is a challenge. Concurrent chemotherapy has become the mainstay of treatment and platinum remains the most effective single agent. Combinations of other agents have not demonstrated significant advantages. The application of angiogenesis inhibitors such as bevacizumab, an antibody inhibiting vascular endothelial growth factor, in metastatic or advanced cervical cancer remains to be evaluated. We present the case of a patient with platinum-resistant recurrent cervical cancer treated with low-dose bevacizumab and carboplatin, with resultant improved disease progression and tolerable toxicity profiles.

Reproductive BioMedicine Online, 2014

Chemotherapy damages the reproductive system by enhancing apoptosis, and evidence suggests that t... more Chemotherapy damages the reproductive system by enhancing apoptosis, and evidence suggests that targeted antiapoptotic therapy may preserve fertility in patients receiving chemotherapy. To investigate the protective effect of sphingosine-1phosphate (S1P) on chemotherapeutic agent-induced ovarian gonadotoxicity, busulfan-treated female mice were pre-treated with low (0.5 mM) and high (2.0 mM) doses of S1P or vehicle 1 h before busulfan injection. In the S1P groups, each mouse was injected with low-dose S1P in one ovary and high-dose S1P in the contralateral ovary. Four weeks later, the ovaries were removed for histological and biochemical examinations. Caspase 3 immunoreactivity was greater in mice treated with busulfan compared with mice pre-treated with S1P, in which more primordial follicles were observed (P < 0.05). The mRNA level of anti-Müllerian hormone was higher in mice pre-treated with S1P than those that received busulfan only, indicating a better ovarian function in mice pre-treated with S1P. No difference was observed in the levels of growth differentiation factor-9 among all groups. In conclusion, S1P protects primordial follicles from chemotherapy-induced gonadotoxicity, and may partially preserve ovarian function.

Journal of Ovarian Research, 2014

Background: Cryopreservation of ovarian tissue has been suggested as an alternative to restore fe... more Background: Cryopreservation of ovarian tissue has been suggested as an alternative to restore fertility for ovarian failure before chemotherapy.

Reproductive Sciences, 2014

Significant follicle loss from frozen ovarian grafts is unavoidable. The authors evaluated the pr... more Significant follicle loss from frozen ovarian grafts is unavoidable. The authors evaluated the protective effects of the antiapoptotic agent sphingosine-1-phosphate (S1P) on vitrified ovarian grafts. Three-week-old sexually immature female FVB mice were divided into 4 groups, fresh, control without S1P, 0.5 mmol/L S1P, and 2 mmol/L S1P. The ovaries were pretreated with S1P for 1 hour and then cryopreserved by modified vitrification. The frozen-thawed ovaries were autotransplanted under the back muscles of mice for 10 days. Expression of apoptosis-related genes encoding caspase 3 and c-Myc was analyzed in the vitrified ovaries and 10 days after transplantation using real-time quantitative polymerase chain reaction. To quantify the ovarian reserve, anti-Müllerian hormone (AMH) levels and follicles were measured in the 10-day vitrified ovarian grafts. Caspase 3 and c-Myc messenger RNA did not differ significantly in the 4 groups after vitrification but was significantly upregulated in the control group after transplantation. The AMH levels and primordial follicle pool were significantly higher in the S1P-treated groups than in the control group but lower than that in the fresh group. The S1P protects vitrified ovarian grafts from ischemic reperfusion injury rather than from vitrification-associated process.

European Journal of Obstetrics & Gynecology and Reproductive Biology, 2010

Archives of Gynecology and Obstetrics, 2010

Umbilical cord abnormalities are accepted as conditions associated with intrauterine fetal demise... more Umbilical cord abnormalities are accepted as conditions associated with intrauterine fetal demise (IUFD), and umbilical cord stricture is most frequently encountered. In addition, although cord entanglement with multiple loops rarely increases the perinatal mortality, it is associated with a signiWcant increase in variable kind of morbidity such as growth restriction. We describe a 27-year-old woman, with a missed abortion history at about 10 weeks' gestation in her Wrst pregnancy, who presented to our outpatient department at 34 4/7 weeks of gestation due to decreased fetal activity during the preceding week. No fetal heart activity and blood Xow had been detected by ultrasonography and pulsed-wave Doppler. A demised fetus with umbilical cord stricture and three loops around abdomen was delivered and was weighted 1,830 g that was below the tenth percentile for the gestational age. Either umbilical cord stricture or entanglement around the body can aVect the development of the fetus and even be lethal. The former might play a more important role in this case. Their etiology and the sequence of the events are still undetermined, and additional evaluation such as autopsy and further research may be needed. In addition, counsel and frequent fetal surveillance should be done in patients with previous IUFD attributed to cord stricture during next pregnancy because of undetermined risk of recurrence.

Objective: Minimally invasive surgery has been the trend in various specialties and continues to ... more Objective: Minimally invasive surgery has been the trend in various specialties and continues to evolve as new technology develops. The development of robotic surgery in gynecology remains in its infancy. The present study reports the first descriptive series of robotic surgery in complicated gynecologic diseases in Taiwan. Materials and Methods: From March 2009 to February 2011, the records of patients undergoing robotic surgery using the da Vinci Surgical System were reviewed for patient demographics, indications, operative time, hospital stay, conversion to laparotomy, and complications. Results: Sixty cases were reviewed in the present study. Forty-nine patients had benign gynecologic diseases, and 11 patients had malignancies. These robot-assisted laparoscopic procedures include nine hysterectomy, 15 subtotal hysterectomy, 13 myomectomy, eight staging operation, two radical hysterectomy, five ovarian cystectomy, one bilateral salpingo-oophorectomy and myomectomy, two resections of deep pelvic endometriosis, one pelvic adhesiolysis, three sacrocolpopexy and one tuboplasty. Thirty-three patients had prior pelvic surgery, and one had a history of pelvic radiotherapy. Adhesiolysis was necessary in 38 patients to complete the whole operation. Robotic myomectomy was easily accomplished in patients with huge uterus or multiple myomas. The suturing of myometrium or cervical stump after ligation of the uterine arteries minimized the blood loss. In addition, it was much easier to dissect severe pelvic adhesions. The dissection of para-aortic lymph nodes can be easily accomplished. All these surgeries were performed smoothly without ureteral, bladder or bowel injury. Conclusion: The present analyses include various complicated gynecologic conditions, which make the estimation of the effectiveness of robotic surgery in each situation individually not appropriate. However, our experiences do show that robotic surgery is feasible and safe for patients with complicated gynecologic diseases.

Taiwanese Journal of Obstetrics and Gynecology, 2012

European journal of gynaecological oncology, 2010

Management of patients with recurrent or advanced cervical cancer is a challenge. Concurrent chem... more Management of patients with recurrent or advanced cervical cancer is a challenge. Concurrent chemotherapy has become the mainstay of treatment and platinum remains the most effective single agent. Combinations of other agents have not demonstrated significant advantages. The application of angiogenesis inhibitors such as bevacizumab, an antibody inhibiting vascular endothelial growth factor, in metastatic or advanced cervical cancer remains to be evaluated. We present the case of a patient with platinum-resistant recurrent cervical cancer treated with low-dose bevacizumab and carboplatin, with resultant improved disease progression and tolerable toxicity profiles.

Reproductive BioMedicine Online, 2014

Chemotherapy damages the reproductive system by enhancing apoptosis, and evidence suggests that t... more Chemotherapy damages the reproductive system by enhancing apoptosis, and evidence suggests that targeted antiapoptotic therapy may preserve fertility in patients receiving chemotherapy. To investigate the protective effect of sphingosine-1phosphate (S1P) on chemotherapeutic agent-induced ovarian gonadotoxicity, busulfan-treated female mice were pre-treated with low (0.5 mM) and high (2.0 mM) doses of S1P or vehicle 1 h before busulfan injection. In the S1P groups, each mouse was injected with low-dose S1P in one ovary and high-dose S1P in the contralateral ovary. Four weeks later, the ovaries were removed for histological and biochemical examinations. Caspase 3 immunoreactivity was greater in mice treated with busulfan compared with mice pre-treated with S1P, in which more primordial follicles were observed (P < 0.05). The mRNA level of anti-Müllerian hormone was higher in mice pre-treated with S1P than those that received busulfan only, indicating a better ovarian function in mice pre-treated with S1P. No difference was observed in the levels of growth differentiation factor-9 among all groups. In conclusion, S1P protects primordial follicles from chemotherapy-induced gonadotoxicity, and may partially preserve ovarian function.

Journal of Ovarian Research, 2014

Background: Cryopreservation of ovarian tissue has been suggested as an alternative to restore fe... more Background: Cryopreservation of ovarian tissue has been suggested as an alternative to restore fertility for ovarian failure before chemotherapy.

Reproductive Sciences, 2014

Significant follicle loss from frozen ovarian grafts is unavoidable. The authors evaluated the pr... more Significant follicle loss from frozen ovarian grafts is unavoidable. The authors evaluated the protective effects of the antiapoptotic agent sphingosine-1-phosphate (S1P) on vitrified ovarian grafts. Three-week-old sexually immature female FVB mice were divided into 4 groups, fresh, control without S1P, 0.5 mmol/L S1P, and 2 mmol/L S1P. The ovaries were pretreated with S1P for 1 hour and then cryopreserved by modified vitrification. The frozen-thawed ovaries were autotransplanted under the back muscles of mice for 10 days. Expression of apoptosis-related genes encoding caspase 3 and c-Myc was analyzed in the vitrified ovaries and 10 days after transplantation using real-time quantitative polymerase chain reaction. To quantify the ovarian reserve, anti-Müllerian hormone (AMH) levels and follicles were measured in the 10-day vitrified ovarian grafts. Caspase 3 and c-Myc messenger RNA did not differ significantly in the 4 groups after vitrification but was significantly upregulated in the control group after transplantation. The AMH levels and primordial follicle pool were significantly higher in the S1P-treated groups than in the control group but lower than that in the fresh group. The S1P protects vitrified ovarian grafts from ischemic reperfusion injury rather than from vitrification-associated process.

European Journal of Obstetrics & Gynecology and Reproductive Biology, 2010

Archives of Gynecology and Obstetrics, 2010

Umbilical cord abnormalities are accepted as conditions associated with intrauterine fetal demise... more Umbilical cord abnormalities are accepted as conditions associated with intrauterine fetal demise (IUFD), and umbilical cord stricture is most frequently encountered. In addition, although cord entanglement with multiple loops rarely increases the perinatal mortality, it is associated with a signiWcant increase in variable kind of morbidity such as growth restriction. We describe a 27-year-old woman, with a missed abortion history at about 10 weeks' gestation in her Wrst pregnancy, who presented to our outpatient department at 34 4/7 weeks of gestation due to decreased fetal activity during the preceding week. No fetal heart activity and blood Xow had been detected by ultrasonography and pulsed-wave Doppler. A demised fetus with umbilical cord stricture and three loops around abdomen was delivered and was weighted 1,830 g that was below the tenth percentile for the gestational age. Either umbilical cord stricture or entanglement around the body can aVect the development of the fetus and even be lethal. The former might play a more important role in this case. Their etiology and the sequence of the events are still undetermined, and additional evaluation such as autopsy and further research may be needed. In addition, counsel and frequent fetal surveillance should be done in patients with previous IUFD attributed to cord stricture during next pregnancy because of undetermined risk of recurrence.

Objective: Minimally invasive surgery has been the trend in various specialties and continues to ... more Objective: Minimally invasive surgery has been the trend in various specialties and continues to evolve as new technology develops. The development of robotic surgery in gynecology remains in its infancy. The present study reports the first descriptive series of robotic surgery in complicated gynecologic diseases in Taiwan. Materials and Methods: From March 2009 to February 2011, the records of patients undergoing robotic surgery using the da Vinci Surgical System were reviewed for patient demographics, indications, operative time, hospital stay, conversion to laparotomy, and complications. Results: Sixty cases were reviewed in the present study. Forty-nine patients had benign gynecologic diseases, and 11 patients had malignancies. These robot-assisted laparoscopic procedures include nine hysterectomy, 15 subtotal hysterectomy, 13 myomectomy, eight staging operation, two radical hysterectomy, five ovarian cystectomy, one bilateral salpingo-oophorectomy and myomectomy, two resections of deep pelvic endometriosis, one pelvic adhesiolysis, three sacrocolpopexy and one tuboplasty. Thirty-three patients had prior pelvic surgery, and one had a history of pelvic radiotherapy. Adhesiolysis was necessary in 38 patients to complete the whole operation. Robotic myomectomy was easily accomplished in patients with huge uterus or multiple myomas. The suturing of myometrium or cervical stump after ligation of the uterine arteries minimized the blood loss. In addition, it was much easier to dissect severe pelvic adhesions. The dissection of para-aortic lymph nodes can be easily accomplished. All these surgeries were performed smoothly without ureteral, bladder or bowel injury. Conclusion: The present analyses include various complicated gynecologic conditions, which make the estimation of the effectiveness of robotic surgery in each situation individually not appropriate. However, our experiences do show that robotic surgery is feasible and safe for patients with complicated gynecologic diseases.